Psilocybin Efficacy With or Without Pimavanserin Pretreatment

Twenty healthy adults (≥21 years old) will be enrolled to evaluate the efficacy of a single oral dose of psilocybin (25 mg) administered with or without pretreatment using oral pimavanserin (34 mg) or placebo. Outcome assessments will occur at 1 week and 1 month following psilocybin administration. The purpose of this study is to clarify the receptor-level mechanisms underlying psilocybin's effects on mood and well-being, along with the associated neurophysiologic signatures. These mechanisms will be examined using psychometric scales, autonomic and fMRI-based neurophysiologic markers, and integrated pharmacokinetic/pharmacodynamic modeling.

NCT Number	NCT07610135
Lead Sponsor	Johns Hopkins University
Conditions	Mood (Psychological Function), Well Being, Mood, Healthy
Enrollment	20 participants
Start Date	2026-07
Primary Completion	2028-06 (estimated)
Study Completion	2028-12 (estimated)
Updated on ClinicalTrials.gov	2026-07-21